Question

I am converting Java into C# and have the following code (see discussion in Java Context about its use). One approach might be to create a separate file/class but is there a C# idom which preserves the intention in the Java code?

   public class Foo {

    // Foo fields and functions
    // ...
        private static class SGroup {
            private static Map<Integer, SGroup> idMap = new HashMap<Integer, SGroup>();

            public SGroup(int id, String type) {
    // ...
            }
        }
    }

Answer 1

Give this a look
http://blogs.msdn.com/oldnewthing/archive/2006/08/01/685248.aspx

I am looking specifically at

In other words, Java inner classes are
syntactic sugar that is not available
to C#. In C#, you have to do it
manually.

If you want, you can create your own
sugar:

class OuterClass {
 ...
 InnerClass NewInnerClass() {
  return new InnerClass(this);
 }
 void SomeFunction() {
  InnerClass i = this.NewInnerClass();
  i.GetOuterString();
 }
}

Where you would want to write in Java
new o.InnerClass(…) you can write in
C# either o.NewInnerClass(…) or new
InnerClass(o, …). Yes, it’s just a
bunch of moving the word new around.
Like I said, it’s just sugar.